U.S. Pat. No. 5,772,717 Kirschner et al. discloses a tempering method using a two phase flow of cryogen for spraying surface layers of an article, such as a glass sheet, with a two phase flow of coolant consisting essentially of a liquid and a vapor. This spraying of the coolant on the surface layers is disclosed as being done so the liquid does not accumulate on the surface layers as a film.
References cited in the above referenced Kirschner et al. patent include U.S. Pat. Nos. 2,026,165 Goodwillie; 2,259,727 Bowers; 3,701,266 Chhisholm; 3,762,902 Wagner et al.; 3,775,087 Ritter, Jr.; 3,869,876 Gardent et al.; and 4,018,590 Imler as well as a publication entitled INTRODUCTION TO CERAMICS by Kingery et al., pp. 830-831, 1976. Additional references cited in a search report for a corresponding European application include U.S. Pat. Nos. 3,801,397 Casserley; 3,883,339 Michalik; 3,929,442 Neely; 4,190,473 Soecknick; and 4,578,102 Colmon; and French patent document 2,650,997.